The invention relates to an apparatus for crimping closures applied on containers. The apparatus is characterized by a mechanism that allows the automatic adjustment of the position of the crimping heads of the apparatus.
It is common practice to commercialize or distribute for use liquid pharmaceutical compositions in vials that are sealed with crimp-type closures. Typically, a crimp-type closure includes a resilient plug member that is surrounded by a metallic sleeve. When the closure is applied on the container, the resilient plug member is inserted in the mouth of the container to create a fluid-tight seal. The metallic sleeve fits outside the mouth of the container and has a length sufficient such as to extend below a radial projection formed on the container and located adjacent to its mouth. The purpose of the sleeve is to lock the closure on the container mouth and prevent the closure from being removed unless the sleeve is torn of otherwise pulled off the container. To lock the sleeve, the container is subjected to a crimping operation. During that crimping operation, the lower extremity of the sleeve is bent radially inwardly such as to interfere with the radial projection on the container neck if an attempt is made to pull the closure off.
Crimp-type closures are usually applied on the containers filled with the medicinal preparation by automatic capping machines. During the capping operation, filled containers are transported to a first processing station where crimp-type closures are dropped onto them. If necessary, a pressure is applied such as to forcibly insert the resilient plug member of the crimp-type closure in the mouth of each container. The last step of the capping operation is to crimp the closures. This is done by a crimping machine that has a revolving turret carrying a plurality of crimping heads, each crimping head being associated with a container to be crimped.
The crimping head comprises a crimping tool that is in the form of a circular blade. The circular blade registers with the closure at the location where the crimp is to be made. The crimping blade is then advanced against the container to initiate the crimping operation. At the same time, the container is rotated about its vertical axis to effect a complete revolution that will complete the crimp. The crimping head is then retracted and the container allowed to proceed toward the next processing station whereupon a further operation is performed such as the application of the label, etc.
A problem associated with existing crimping machines is the necessity to manually adjust the position of each crimping head on the revolving turret when the machine is being set up for a new production run. Since different size containers require a different geometrical relationship between the crimping tool and the neck of the container, the position of each crimping head on the revolving turret must be adjusted manually. This operation is time consuming. In addition, the operation must be performed by experienced personnel to avoid situations where one or more of the crimping heads are improperly positioned thereby resulting in improper crimping when the machine is run.
Against this background, it clearly appears that there is a need in the industry to provide an automatic crimping machine on which the crimping heads can be automatically adjusted.
In a broad aspect, the invention provides a crimping apparatus comprising a revolving turret, a cam, and a plurality of crimping heads supported by the revolving turret. Each crimping head includes a cam follower for engaging one of a plurality of possible cam follower receiving positions defined by the cam. When the revolving turret is in motion, the cam follower tracks the selected cam follower receiving position that is characterized by a certain profile. The profile determines the movement imparted to the crimping head by the cam follower. The cam follower can be located at a different cam receiving position on the cam by displacing the cam and the revolving turret one relative to the other.
The ability to set the cam follower at different cam follower receiving positions allows to quickly perform the necessary changes to the apparatus so as to set it for a production run. For instance, each cam follower receiving position can have a unique profile that makes it suitable for use with a particular container size or type. Thus, by selecting the proper cam follower receiving position the adjustment of the machine is quickly effected.
In a specific non-limiting example of implementation, the revolving turret and the cam are selectively displaceable one relative to the other along the axis of revolution of the revolving turret. More specifically, the axis of revolution is generally vertical. The cam is tapered and defines a plurality of cam follower receiving positions arranged along the direction of taper. A cam follower receiving position is the portion of the cam surface that the cam follower tracks during the revolution of the revolving turret. This portion of the cam surface is characterized by a certain profile. By displacing the revolving turret with relative to the cam, the cam follower engages a different portion of the cam, hence it tracks a different cam follower engaging position.
Under this specific and non-limiting example of implementation, the crimping apparatus comprises a second revolving turret which underlies the first revolving turret and which is associated with the first revolving turret. The second revolving turret, which rotates at the same speed as the first revolving turret, comprises a plurality of container seats which are associated with respective crimping heads. In operation, each container seat supports a container while its associated crimping head crimps the closure of the container.
The crimping heads, which are mounted to the first revolving turret at constant angular intervals, each include a substantially vertically extending body. Each crimping head""s respective cam follower is mounted to an upper end of the body while the lower end of that same body includes an arm supporting a crimping too; the latter being typically in the form of a disk.